The first rocket will take five minutes to hit London. You have six minutes to stop the second one.

Rudi Graf, an engineer who dreamed of sending rockets to the Moon, ends up working alongside Wernher von Braun for the Nazis, bombing London with V2 rockets. The SS exerts increasingly suffocating control over this operation, and Graf must muster all his strength to keep in line with the party's directives. And when rumors of a traitor start circulating among high-ranking German officers, Graf becomes the prime suspect.

Kay Caton-Walsh is also caught in the whirlwind of war. When her affair with her lover, an RAF officer, is revealed amidst a V2 rocket bombing, she volunteers to move to a small town in Belgium, where, along with other WAAF members, she hopes to locate and destroy the launch sites of the deadly V2 rockets. However, at this stage of the war, it's hard to know whom to trust. If there is anyone at all…

As the casualty count rises daily, these two stories unfold in parallel with the German ballistic campaign, and Graf's fate will inevitably collide with Kay's destiny.